An Overview of Renal Cell Carcinoma Hallmarks, Drug Resistance, and Adjuvant Therapies.

Renal neoplasms are highlighted as one of the 10 most common types of cancer. Renal cell carcinoma (RCC) is the most common type of renal cancer, considered the seventh most common type of cancer in the Western world. The most frequently altered genes described as altered are VHL, PBRM1, SETD2, KDM5C, PTEN, BAP1, mTOR, TP53, TCEB1 (ELOC), SMARCA4, ARID1A, and PIK3CA. RCC therapies can be classified in three groups: monoclonal antibodies, tyrosine kinase inhibitors, and mTOR inhibitors. Besides, there are targeted agents to treat RCC. However, frequently patients present side effects and resistance. Even though many multidrug resistance mechanisms already have been reported to RCC, studies focused on revealing new biomarkers as well as more effective antitumor therapies with no or low side effects are very important. Some studies reported that natural products, such as honey, epigallocatechin-3-gallate (EGCG), curcumin, resveratrol, and englerin A showed antitumor activity against RCC. Moreover, nanoscience is another strategy to improve RCC treatment and reduce the side effects due to the improvement in pharmacokinetics and reduction of toxicities of chemotherapies. Taking this into account, we conducted a systemic review of recent research findings on RCC hallmarks, drug resistance, and adjuvant therapies. In conclusion, a range of studies reported that RCC is characterized by high incidence and increased mortality rates because of the development of resistance to standard therapies. Given the importance of improving RCC treatment and reducing adverse effects, nanoscience and natural products can be included in therapeutic strategies.

Randia ferox (Cham & Schltdl) DC.: phytochemical composition, in vitro cyto- and genotoxicity analyses.

Randia ferox is a Brazilian native species used in folk medicine. Scientific information regarding the toxicology and phytochemistry of this plant remains unclear. We aimed to produce a R. ferox extract, identify its chemical matrix, and evaluate its safety profile. The extract chemical composition was accessed through UHPLC-MS/MS. Mononuclear cells, erythrocytes, fibroblasts, macrophages, and kidney cells were subjected to extract concentration-response curve testing. The cellular viability, proliferation, dsDNA release, reactive oxygen species (ROS), nitric oxide (NO), hemolysis, and DNA damage were determined. Ten molecules were found in the extract matrix. Most of the tested concentrations can be considered safe. Cellular viability, proliferation, dsDNA release, and NO remained at similar levels to the control. The extract increased ROS in macrophages. None of the tested concentrations induced DNA damage or hemolysis. The data suggest R. ferox extract contains several bioactive molecules and has a safety profile in vitro.

Antioxidant and cytoprotective effects of avocado oil and extract (Persea americana Mill) against rotenone using monkey kidney epithelial cells (Vero).

Oxidative stress is known to be involved in development of numerous diseases including cardiovascular, respiratory, renal, kidney and cancer. Thus, investigations that mimic oxidative stress in vitro may play an important role to find new strategies to control oxidative stress and subsequent consequences are important. Rotenone, widely used as a pesticide has been used as a model to simulate oxidative stress. However, this chemical was found to produce several diseases. Therefore, the aim of this study was to investigate the antioxidant and cytoprotective effect of avocado (Persea americana Mill) extract and oil in monkey kidney epithelial cells (VERO) exposed to rotenone. VERO cells were exposed to IC50 of rotenone in conjunction with different concentrations of avocado extract and oil (ranging from 1 to 1000 µg/ml), for 24 hr. Subsequently, cell viability and oxidative metabolism were assessed. Data demonstrated that avocado extract and oil in the presence of rotenone increased cellular viability at all tested concentrations compared to cells exposed only to rotenone. In addition, extract and avocado oil exhibited antioxidant action as evidenced by decreased levels of reactive oxygen species (ROS), superoxide ion, and lipid peroxidation, generated by rotenone. Further, avocado extract and oil appeared to be safe, since these compounds did not affect cell viability and or generate oxidative stress. Therefore, avocado appears to display a promising antioxidant potential by decreasing oxidative stress.

Açaí (Euterpe oleracea Mart.) as a Potential Anti-neuroinflammatory Agent: NLRP3 Priming and Activating Signal Pathway Modulation.

Neurological disorders have been demonstrated to be associated with mitochondrial dysfunction. This impairment may lead to oxidative stress and neuroinflammation, specifically promoted by NLRP3 expression. Açaí (Euterpe oleracea Mart.) has been studied in this field, since it presents important biological activities. We investigated açaí extract's anti-neuroinflammatory capacity, through NLRP3 inflammasome modulation. Microglia (EOC 13.31) were exposed to LPS and nigericin, as agents of inflammatory induction, and treated with açaí extract. Additionally, we used lithium (Li) as an anti-inflammatory control. Three different experiment models were conducted: (1) isolated NLRP3 priming and activation signals; (2) combined NLRP3 priming and activation signals followed by açaí extract as a therapeutic agent; and (3) combined NLRP3 priming and activation signals with açaí extract as a preventive agent. Cells exposed to 0.1 µg/mL of LPS presented high proliferation and increased levels of NO, and ROS, while 0.1 µg/mL of açaí extract was capable to reduce cellular proliferation and recover levels of NO and ROS. Primed and activated cells presented increased levels of NLRP3, caspase-1, and IL-1ß, while açaí, Li, and orientin treatments reversed this impairment. We found that açaí, Li, and orientin were effective prophylactic treatments. Preventative treatment with Li and orientin was unable to avoid overexpression of IL-1ß compared to the positive control. However, orientin downregulated NLRP3 and caspase-1. Lastly, primed and activated cells impaired ATP production, which was prevented by pre-treatment with açaí, Li, and orientin. In conclusion, we suggest that açaí could be a potential agent to treat or prevent neuropsychiatric diseases related to neuroinflammation.

In Vitro Biological Properties of Solanum sessiliflorum (Dunal), an Amazonian Fruit.

Solanum sessiliflorum is an Amazonian fruit (cubiu) that has been domesticated since pre-Colombian era. It is also used in folk medicine to treat some clinical conditions. This investigation chemically characterized and analyzed the in vitro antioxidant and antitumoral effect of a cubiu pulp/seed hydroalcoholic extract. Cubiu extract was chemically characterized by high-performance liquid chromatography with diode array detector (HPLC-DAD), its antioxidant capacity measured by 2.2-diphenyl-1-picrylhydrazyl (DPPH) assay, and the following complementary in vitro protocols were performed: (1) cytoprotective effect of cubiu on human peripheral blood mononuclear cells (PBMCs) exposed to H2O2, a genotoxic and procarcinogen molecule; (2) effect of cubiu on low density lipoproteins oxidation; and (3) cytotoxic and antiproliferative effect on breast (MCF-7) and colorectal (HT-29) cancer cell lines. Biochemical and flow cytometry analyses were conducted in these protocols. Cubiu extract presented high concentrations of caffeic and gallic acids, beta-carotene, catechin, quercetin, and rutin, and its antioxidant capacity was confirmed. Cubiu attenuated H2O2 cytotoxicity on PBMCs, presented lowering effect on LDL oxidation, and induced mortality and proliferative inhibition of colorectal cancer cells. In cancer cells, cubiu extract at 10 µg/mL showed similar effects to 5-fluorouracil chemo drug reducing its viability and frequency of S-phase, indicating that cells are undergoing mitosis. In summary, despite the limitations of in vitro protocols, our results suggest that cubiu has several biological properties that affect human health.

Guarana improves behavior and inflammatory alterations triggered by methylmercury exposure: an in vivo fruit fly and in vitro neural cells study.

Methylmercury (MeHg) is a well-known environmental pollutant associated with neurological and developmental deficits in animals and humans. However, epidemiological data showed that people living in the Amazon region although exposed to MeHg do not present these effects probably due to the protective effect of certain foods. We hypothesized here if guarana, a highly caffeinated fruit and consumed on a daily basis by Amazon people, could have some protective effect against MeHg toxicity using two complementary approaches. To assess locomotor impairment and sleep disruption, we used fruit fly (Drosophila melanogaster) model, and to evaluate neuroinflammation, we used human SH-SY5Y neural cells by measuring inflammatory cytokines levels. Results showed that guarana had a protective effect on the locomotor activity of male fruit flies reducing the excessive sleepiness caused by MeHg and increasing daily activity. Also, guarana increased the viability of flies and attenuated neural cells mortality. In addition, guarana reduced all pro-inflammatory cytokines levels increased by MeHg, along with caspase-1, caspase -3, caspase-8, and 8-dOHG levels, whereas increased the anti-inflammatory (IL-10) cytokine levels, which was decreased by MeHg. Our study provides new insights on the protective effects of guarana on the viability, locomotor activity, sleep, and activity patterns in vivo and the in vitro neuronal anti-inflammatory effect against MeHg toxicity.

Tea tree oil presents in vitro antitumor activity on breast cancer cells without cytotoxic effects on fibroblasts and on peripheral blood mononuclear cells.

The purpose of this study was to investigate some possible mechanisms underlying the in vitro antitumor activity of tea tree oil (TTO) on human and mouse breast cancer cells (MCF-7 and 4T1, respectively) and its cytotoxicity on fibroblasts (HFF-1) and on peripheral blood mononuclear cells (PBMCs). TTO High-Resolution Gas Chromatography (HRGC) showed seventeen main constituents, such as Terpinen-4-ol, γ-Terpinene, and α-Terpinene. High TTO concentrations (≥ 600 µg/mL) showed a remarkable antitumor activity, decreasing cell viability and cell proliferation of MCF-7 and 4T1 cells. TTO at 300 µg/mL increased the number of MCF-7 cells in the early stages of apoptosis and increased the BAX/BCL-2 genes ratio. TTO, mainly at 300 µg/mL, decreased cell growth and arrested MCF-7 cells in the S phase of the cell cycle. Lower antitumor concentrations (≤300 µg/mL) evaluated in MCF-7 and 4T1 cells were not cytotoxic to PBMCs and HFF-1. Also, TTO (300 µg/mL) was able to induce cell proliferation in fibroblasts after 72 h, indicating non-cytotoxic effect in these cells. TTO exhibited in vitro antitumor effect on MCF-7 and 4T1 cells by decreasing cell viability and modulating apoptotic pathways and cell cycle arrestment of MCF-7 cells. In this sense, our study provides new perspectives on the potential use of TTO for the development of new alternative therapies to treat topically locally advanced breast cancer (LABC).

A chemical compound based on methylxanthine-polyphenols lowers nitric oxide levels and increases post-thaw human sperm viability.

We produced a new chemical compound based on methylxanthines and polyphenols (CCMP) present in the chemical matrix of guaraná (Paullinia cupana), a seed extract with antioxidant properties. After supplementation with the standard extract of resveratrol, a well documented antioxidant found in other plant sources, we investigated whether this resveratrol-enriched compound could improve sperm viability and modulate differentially reactive oxygen species (ROS) and nitric oxide (NO) levels in thawed sperm. Sperm samples obtained from healthy young donors were treated with different concentrations of guaraná extract (0.1, 1, 5 or 10 mg/ml) and cells were frozen at -80°C for 24 h. In addition, the potential protective effects of guaraná treatment on sperm treated with pro-oxidant compound (200 µM hydrogen peroxide, H2O2) were assessed. Samples were also exposed to three concentrations of CCMP before being frozen in liquid nitrogen (-196°C) or in an ultrafreezer (-80°C) for 24 h, and both pre-freezing and post-thaw measurements of viability and oxidative stress were performed. Guaraná supplementation at 10 mg/ml significantly increased post-thaw viability and decreased oxidative metabolism of the sperm. Moreover, selected concentrations of CCMP improved viability and oxidative metabolism in sperm samples pre-freezing. Furthermore, CCMP showed cryoprotective activity by increasing viability and decreasing oxidative stress in post-thaw samples. In summary, these findings suggested that CCMP supplementation acts as a cryoprotectant to modulate ROS and NO levels in thawed sperm. CCMP could be used to enhance sperm quality and reproductive success.

Neuroprotective Effects of Açaí (Euterpe oleracea Mart.) against Rotenone In Vitro Exposure.

Neuropsychiatric diseases, such as bipolar disorder (BD) and schizophrenia (SCZ), have a very complex pathophysiology. Several current studies describe an association between psychiatric illness and mitochondrial dysfunction and consequent cellular modifications, including lipid, protein, and DNA damage, caused by cellular oxidative stress. Euterpe oleracea (açaí) is a powerful antioxidant fruit. Açaí is an Amazonian palm fruit primarily found in the lowlands of the Amazonian rainforest, particularly in the floodplains of the Amazon River. Given this proposed association, this study analyzed the potential in vitro neuropharmacological effect of Euterpe oleracea (açaí) extract in the modulation of mitochondrial function and oxidative metabolism. SH-SY5Y cells were treated with rotenone to induce mitochondrial complex I dysfunction and before and after we exposed the cells to açaí extract at 5 µg/mL. Treated and untreated cells were then analyzed by spectrophotometric, fluorescent, immunological, and molecular assays. The results showed that açaí extract can potentially increase protein amount and enzyme activity of mitochondrial complex I, mainly through NDUFS7 and NDUFS8 overexpression. Açaí extract was also able to decrease cell reactive oxygen species levels and lipid peroxidation. We thus suggest açaí as a potential candidate for drug development and a possible alternative BD therapy.

Tucumã fruit extracts (Astrocaryum aculeatum Meyer) decrease cytotoxic effects of hydrogen peroxide on human lymphocytes.

This study quantifies the bioactive molecules in and determines the in vitro protective effect of ethanolic extracts isolated from the peel and pulp of tucumã (Astrocaryum aculeatum, Mart.), an Amazonian fruit rich in carotenoids. The cytoprotective effect of tucumã was evaluated in lymphocyte cultures exposed to H2O2 using spectrophotometric, fluorimetric, and immunoassay assays. The results confirmed that tucumã pulp extract is rich in ß-carotene and quercetin, as previously described in the literature. However, high levels of these compounds were also found in tucumã peel extract. The extracts also contained significant amounts rutin, gallic acid, caffeic acid, and chlorogenic acid. Despite quantitative differences in the concentration of these bioactive molecules, both extracts increased the viability of cells exposed to H2O2 in concentrations ranging from 300 to 900 µg/mL. Caspases 1, 3, and 8 decreased significantly in cells concomitantly exposed to H2O2 and these extracts, indicating that tucumã cryoprotection involves apoptosis modulation.